Minnesota Bridge that Collapsed Found â€œStructurally Deficientâ€ in 2005

The Minnesota I-35 W Bridge that collapsed last night was rated â€œstructurally deficientâ€ after a 2005 inspection, according to the US Department of Transportationâ€™s Bridge Inventory database, and the report recommended that the structure be scheduled for replacement. Meanwhile, Minnesota authorities said that they expected to pull many more dead from the Mississippi River as recovery efforts continued following the Minnesota bridge collapse, and the stateâ€™s governor ordered inspections for other Minnesota bridges.

After the bridge in Minnesota collapsed a spokesperson for the Minnesota Department of Transportation (MNDOT) told the Minneapolis Star Tribune that the agency was aware of the 2005 evaluation of the bridge, but would not make further comment. The 40-year-old I-35 W Bridge received a score of 50 in the evaluation, which means that a bridge might need to be replaced. The evaluation also gave the bridgeâ€™s structural components a grade of 4 out of 9. That grade included evaluations of the I-35 Bridgeâ€™s deck, piers, abutments and footings. A 2001 report by the Minnesota University Center for Transportation Studies that evaluated the bridgeâ€™s trusses found evidence of many â€œpoor fatigue detailsâ€. At that time, the 2001 report concluded that the I-35 W Bridge was not in danger of fatigue cracking, but it did recommend that the trusses be inspected every two years. The 2001 report also said that certain high stress areas should be inspected every six months. Minnesota Gov. Tim Pawlenty said on Wednesday night that the I-35 W Bridge had been inspected in 2005 and 2006, but that no structural deficiencies were found.

Earlier today, the Governor ordered inspections of all Minnesota bridges with the same design structure as the I-35 W Bridge. According to the Minneapolis Riverfront District Web site, the I-35 W Bridge was a steel arch bridge. Its longest span stretched 458 feet over the river, and it was constructed with no mid-river piers to facilitate river traffic.

Recovery efforts were continuing today, and rescue officials said that they expected that the effort would take at least five days. The twisted metal and concrete debris in the river made for slow-going, officials said, especially because so many victims had been pinned under debris. The Mississippi Riverâ€™s strong current was also making conditions difficult for drivers. At todayâ€™s news briefing, they confirmed that more bodies had been recovered, but would not say how many. Between 20 and 30 people were reported missing, and relatives of the missing were gathered in a hotel awaiting word of their loved ones.

The National Transportation Safety Board (NTSB) began its investigation today. NTSB Chairman Mark Rosenker vowed that his agency would get to the bottom of the bridge collapse, but warned that it could be a year before the NTSB reached any definitive conclusion. Investigators said that they planned to reconstruct the bridge in a warehouse or hanger, and were trying to preserve as many pieces as possible.

The Federal government also announced that it would provide $5 million in aid to the state of Minnesota for cleanup and recovery. It could take as long as two years to replace the I-35 W Bridge. The bridge was one of the main corridors in the Minneapolis/St. Paul area and carried as many as 140,000 cars each day.